Grade setting and surveyor rod

ABSTRACT

A rod or measuring instrument which has a plurality of telescoping tubes having measuring scales on the periphery of said tubes, means for locking said telescoping tubes at any random length, said locking means including a cut away portion at the inner end of each inside tube of said telescoping tubes and an inclined substantially crescent shaped channel formed in said cut away portion of said tube, and a ball or a roller fitted within said channel which ball or roller is free to roll towards a narrow end of said channel when the tubes are turned, thereby wedging said tubes together; and plugs mounted in the ends of the outer tubes.

Heater 51 Oct. 2, 1973 l l GRADE SETTING AND SURVEYOR ROD [76] Inventor:Paul Edward Heater, Santa Rosa,

Calif.

[22] Filed: June 14, 1971 [2l] Appl. No.: 152,747

Related U.S. Application Data [63] Continuation-impart of Ser. No.870,211, March 30,

I970, abandoned.

6/1944 ll/l938 Switzerland 287/58 CT Great Britain 33/l6l PrimaryExaminer-William D. Martin, Jr. An0rneyGeorge B. White [57] ABSTRACT Arod or measuring instrument which has a plurality of telescoping tubeshaving measuring scales on the periphery of said tubes, means forlocking said telescoping tubes at any random length, said locking meansincluding a cut away portion at the inner end of each inside tube ofsaid telescoping tubes and an inclined substantially crescent shapedchannel formed in said cut away portion of said tube, and a ball or aroller fitted within said channel which ball or roller is free to rolltowards a narrow end of said channel when the tubes are turned, therebywedging said tubes together; and plugs mounted in the ends of the outertubes.

4 Claims, 8 Drawing Figures PMENTEU w 2W SHEET 2 OF 2 INVENTOR PoulHeater 1 GRADE SETTING AND SURVEYOR ROD BACKGROUND OF THE INVENTION Thisinvention pertains to a measuring instrument that would be of particularuse to field engineers, surveyors, and other trades needing a long,rigid measuring device.

All the currently available equipment along these lines are heavy,cumbersome and expensive. Because of that fact, many field engineersmake their own measuring instruments.

It is often desirable to have an instrument of great length but they areunwieldy and awkward much of the time when this great length is notused. An extendable measuring instrument which is light yet strong wouldbe of great convenience, but one whose overall length could be extendedin a variable manner and locked into position quickly would be evenbetter.

Having an instrument capable of achieving a great length would in manycases eliminate the need for using a tape measure and so make for rapidmeasurements.

Because there is an unfilled need for such a versatile measuringinstrument, there will be a ready market.

It is an object of this invention to provide a needed telescoping rodsuch as a measuring instrument, which is light, rigid, durable, andeconomical and which can be quickly locked at any selected overalllength by a simple turn of the telescopic part.

A still further object is to incorporate a level bubble in the measuringinstrument to provide a long and extendable level in the same unit.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of acomplete grade setting rod fully extended and broken at the midpoint ofthe interior and exterior tubes.

FIG. 2 is a cross-section drawing of the interior and exterior tubes,illustrating the locking mechanism and the sealed end of the tubes.

FIG. 3 is a cross-section of the uppermost end of the interior tube,showing the level bubble placement -and sealed end of the tube.

FIG. 4 is a sectional end view of the internal locking mechanism.

FIG. 5 is a fragmental isometric view of the telescoping portion of therods showing a roller held in a wedging channel.

FIG. 6 is a cross-sectional view taken through. the roller and thechannel.

FIG. 7 is an isometric view of the magnetically held roller in thewedging channel of the telescoping member.

FIG. 8 is a cross-sectional view through the magnetically held roller inthe wedging channel.

DETAILED DESCRIPTION While numerous tubular measuring devices can bemade using the principles of this invention, the illustrative embodimentherein is in the form of a grade setting rod, wherein a )8 inch tube 11is fitted inside a 34 inch tube 12. In this embodiment anodized aluminumtubes 6 feet in length were used.

On opposite sides of the tubes 11 and 12 are printed engineers scalescalibrated in hundredths l4 and tenths 15 of a foot. The foot numerals16 are printed in larger sizes and a contrasting color.

These markings and printed scales could in a similar fashion be inches,centimeters, or any specialized form of linear measurement.

The outer tube 12 is graduated up to 6 feet. The inner tube 11 continuesin the same manner up to eleven and eight tenths feet when it is fullyextended. The inner tube 1 l, by use of an interior locking device,hereinafter described, may be locked into any position along its length.I

The locking mechanism shown in FIGS. 1 to 4 inclusive, is made byinserting a metal plug 17 into the inner tube 11 then inletting a groovethrough the tube 11 and the plug 17 to create a tapering, curvingchannel 18 along the base of the inner tube 11 and placing a bearingball 19 of appropriate size in the channel, as in FIG. 4. The inner tube11 is fitted into the exterior tube 12, the inner tube 11 when rotatedwill move the ball 19 along the channel 18 until it reaches the shallowend of the groove whereupon it wedges against the wall of the outer tube12 and is pressed into the inner tube 11, thereby locking tubes togetherat that length. The tubes can be quickly and easily released fromposition by rotating the tubes in the opposite direction.

The base of the outer tube 12 is closed with a metal plug 22. All'metalplugs are press fit and cemented in.

In order to prevent the inner tube 11 from being free to escape, theouter tube 12 is necked down near the pen end portion 23. Differentdiameters of tubes could be used andthe number of extensions increasedusing the principles of this invention.

In order to adapt this measuring rod to the needs of the trade a bubblelevel 21 is placed in the upper end of the inner tube 11 using a durablequick setting compound 20 to hold the level and seal the end of the tube1 1.

In the form shown in FIGS. 5 and 6, the cut away portion 31 is cut onthree sides only and the tongue 32 is bent about its uncut edge inwardlyof the tube 11 to form the wedging channel. A tubular roller 33 has awire loop 34 extended therethrough which is placed over the tongue 32from its free end inwardly to hold the roller 33 in place. As the innertube 11 is rotated in clockwise direction, viewing FIG. 5, the rollerroles to the wider portion of the channel and releases the inner tube11. When the inner tube 11 is turned in contra-clockwise direction, orwhen the outer tube 12 is turned in a clockwise direction viewing FIG.5, the roller 33 is rolled to the shallow end of the channel guide andis wedged tightly between the tubes to hold them in adjusted position.

The form shown in FIGS. 7 and 8 operates in the same manner as theembodiment described in FIGS. 5

and 6 except that the wire loop 34 is omitted and the roller 36 is heldin the widest portion of the channel by a permanent magnet 37.

The use of graduated size tubes in combination with the herein wedginglocking mechanisms, together with imprinted and durable lineargraduations, constitutes the basic fundamentals of this invention andresults in a clearly new and novel measuring device, together with thefeature that the rolling element, namely the ball or roller, iscompletely contained in the deeper portion of the guide channel in thereleasing position and is gradually lifted from said guide channel intowedging contact with the inner periphery of the outer tube by therelative turning of the tubes into locked position.

I claim:

1. A telescoping instrument comprising,

a plurality of telescoping tubes, including at least one outside tubeand one inside tube,

means for locking said telescoping tubes at any selected random length,

an inwardly inclined guide adjacent the inner end of the inner tubeformed by a cut away portion of the wall of the inside tube cut on threesides thereof and bent inwardly of said inside tube,

the opposite cut away side edges and said guide forming a guide channel,

a rolling element within said channel and on said inclined guide beingfree to roll on said inclined guide in said channel radially outwardlyof said inner tube when the tubes are turned in one direction therebywedging said tubes together, and to roll from said narrow peripheral endinwardly to the deepest portion of said channel when the tubes areturned in the opposite direction thereby to free said tubes fortelescopic adjustment, said rolling element being completelywithdrawable into said deepest portion of said channel within theperiphery of said inside tube. 2. The telescoping instrument specifiedin claim 1, and

said rolling element being a roller freely rolling on said guidesurface. 3. The telescoping instrument specified in claim and saidroller being tubular and a loop extended through said roller and aroundsaid inwardly bent guide for rotatably holding said roller in saidchannel. 4. The telescoping instrument specified in claim 2, and

a permanent magnet at said deepest portion of said channel for attachingsaid roller at said deepest portion.

1. A telescoping instrument comprising, a plurality of telescopingtubes, including at least one outside tube and one inside tube, meansfor locking said telescoping tubes at any selected random length, aninwardly inclined guide adjacent the inner end of the inner tube formedby a cut away portion of the wall of the inside tube cut on three sidesthereof and bent inwardly of said inside tube, the opposite cut awayside edges and said guide forming a guide channel, a rolling elementwithin Said channel and on said inclined guide being free to roll onsaid inclined guide in said channel radially outwardly of said innertube when the tubes are turned in one direction thereby wedging saidtubes together, and to roll from said narrow peripheral end inwardly tothe deepest portion of said channel when the tubes are turned in theopposite direction thereby to free said tubes for telescopic adjustment,said rolling element being completely withdrawable into said deepestportion of said channel within the periphery of said inside tube.
 2. Thetelescoping instrument specified in claim 1, and said rolling elementbeing a roller freely rolling on said guide surface.
 3. The telescopinginstrument specified in claim 2, and said roller being tubular and aloop extended through said roller and around said inwardly bent guidefor rotatably holding said roller in said channel.
 4. The telescopinginstrument specified in claim 2, and a permanent magnet at said deepestportion of said channel for attaching said roller at said deepestportion.